// Emacs style mode select   -*- C++ -*- 
//-----------------------------------------------------------------------------
//
// $Id:$
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This source is available for distribution and/or modification
// only under the terms of the DOOM Source Code License as
// published by id Software. All rights reserved.
//
// The source is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// FITNESS FOR A PARTICULAR PURPOSE. See the DOOM Source Code License
// for more details.
//
// $Log:$
//
// DESCRIPTION:
//	DOOM main program (D_DoomMain) and game loop (D_DoomLoop),
//	plus functions to determine game mode (shareware, registered),
//	parse command line parameters, configure game parameters (turbo),
//	and call the startup functions.
//
//-----------------------------------------------------------------------------

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "doomdef.h"
#include "doomstat.h"

#include "dstrings.h"

#include "z_zone.h"
#include "w_wad.h"
#include "v_video.h"

#include "f_finale.h"
#include "f_wipe.h"

#include "m_misc.h"
#include "m_menu.h"

#include "i_system.h"
#include "i_video.h"

#include "g_game.h"

#include "hu_stuff.h"
#include "wi_stuff.h"
#include "st_stuff.h"
#include "am_map.h"

#include "p_setup.h"
#include "r_local.h"


#include "d_main.h"

//
// D-DoomLoop()
// Not a globally visible function,
//  just included for source reference,
//  called by D_DoomMain, never exits.
// Manages timing and IO,
//  calls all ?_Responder, ?_Ticker, and ?_Drawer,
//  calls I_GetTime, I_StartFrame, and I_StartTic
//
void D_DoomLoop (void);


char*		wadfiles[MAXWADFILES];


boolean		devparm;	// started game with -devparm
boolean         nomonsters;	// checkparm of -nomonsters
boolean         respawnparm;	// checkparm of -respawn
boolean         fastparm;	// checkparm of -fast

boolean         drone;

boolean		singletics = false; // debug flag to cancel adaptiveness

extern  boolean	inhelpscreens;

skill_t		startskill;
int             startepisode;
int		startmap;
boolean		autostart;

boolean		advancedemo;

char		wadfile[1024];		// primary wad file
char		mapdir[1024];           // directory of development maps
char		basedefault[1024];      // default file

void D_CheckNetGame (void);
void D_ProcessEvents (void);
void G_BuildTiccmd (ticcmd_t* cmd);
void D_DoAdvanceDemo (void);

//
// EVENT HANDLING
//
// Events are asynchronous inputs generally generated by the game user.
// Events can be discarded if no responder claims them
//
event_t         events[MAXEVENTS];
int             eventhead;
int 		eventtail;


//
// D_PostEvent
// Called by the I/O functions when input is detected
//
void D_PostEvent (event_t* ev)
{
    events[eventhead] = *ev;
    eventhead = (++eventhead)&(MAXEVENTS-1);
}


//
// D_ProcessEvents
// Send all the events of the given timestamp down the responder chain
//
void D_ProcessEvents (void)
{
    event_t*	ev;
	
    for ( ; eventtail != eventhead ; eventtail = (++eventtail)&(MAXEVENTS-1) )
    {
	ev = &events[eventtail];
	if (M_Responder (ev))
	    continue;               // menu ate the event
	G_Responder (ev);
    }
}




//
// D_Display
//  draw current display, possibly wiping it from the previous
//

// wipegamestate can be set to -1 to force a wipe on the next draw
gamestate_t     wipegamestate = GS_DEMOSCREEN;
extern  boolean setsizeneeded;
extern  int             showMessages;
void R_ExecuteSetViewSize (void);

void D_Display (void)
{
    static  boolean		viewactivestate = false;
    static  boolean		menuactivestate = false;
    static  boolean		inhelpscreensstate = false;
    static  boolean		fullscreen = false;
    static  gamestate_t		oldgamestate = -1;
    static  int			borderdrawcount;
    int				nowtime;
    int				tics;
    int				wipestart;
    int				y;
    boolean			done;
    boolean			wipe;
    boolean			redrawsbar;

    if (nodrawers)
	return;                    // for comparative timing / profiling
		
    redrawsbar = false;
    
    // change the view size if needed
    if (setsizeneeded)
    {
	R_ExecuteSetViewSize ();
	oldgamestate = -1;                      // force background redraw
	borderdrawcount = 3;
    }

    // save the current screen if about to wipe
    if (gamestate != wipegamestate)
    {
	wipe = true;
	wipe_StartScreen(0, 0, SCREENWIDTH, SCREENHEIGHT);
    }
    else
	wipe = false;

    if (gamestate == GS_LEVEL && gametic)
	HU_Erase();
    
    // do buffered drawing
    switch (gamestate)
    {
      case GS_LEVEL:
	if (!gametic)
	    break;
	if (automapactive)
	    AM_Drawer ();
	if (wipe || (viewheight != 200 && fullscreen) )
	    redrawsbar = true;
	if (inhelpscreensstate && !inhelpscreens)
	    redrawsbar = true;              // just put away the help screen
	ST_Drawer (viewheight == 200, redrawsbar );
	fullscreen = viewheight == 200;
	break;

      case GS_INTERMISSION:
	WI_Drawer ();
	break;

      case GS_FINALE:
	F_Drawer ();
	break;

      case GS_DEMOSCREEN:
	D_PageDrawer ();
	break;
    }
    
    // draw buffered stuff to screen
    I_UpdateNoBlit ();
    
    // draw the view directly
    if (gamestate == GS_LEVEL && !automapactive && gametic)
	R_RenderPlayerView (&players[displayplayer]);

    if (gamestate == GS_LEVEL && gametic)
	HU_Drawer ();
    
    // clean up border stuff
    if (gamestate != oldgamestate && gamestate != GS_LEVEL)
	I_SetPalette (W_CacheLumpName ("PLAYPAL",PU_CACHE));

    // see if the border needs to be initially drawn
    if (gamestate == GS_LEVEL && oldgamestate != GS_LEVEL)
    {
	viewactivestate = false;        // view was not active
	R_FillBackScreen ();    // draw the pattern into the back screen
    }

    // see if the border needs to be updated to the screen
    if (gamestate == GS_LEVEL && !automapactive && scaledviewwidth != 320)
    {
	if (menuactive || menuactivestate || !viewactivestate)
	    borderdrawcount = 3;
	if (borderdrawcount)
	{
	    R_DrawViewBorder ();    // erase old menu stuff
	    borderdrawcount--;
	}

    }

    menuactivestate = menuactive;
    viewactivestate = viewactive;
    inhelpscreensstate = inhelpscreens;
    oldgamestate = wipegamestate = gamestate;
    
    // draw pause pic
    if (paused)
    {
	if (automapactive)
	    y = 4;
	else
	    y = viewwindowy+4;
	V_DrawPatchDirect(viewwindowx+(scaledviewwidth-68)/2,
			  y,0,W_CacheLumpName ("M_PAUSE", PU_CACHE));
    }


    // menus go directly to the screen
    M_Drawer ();          // menu is drawn even on top of everything
    NetUpdate ();         // send out any new accumulation


    // normal update
    if (!wipe)
    {
	I_FinishUpdate ();              // page flip or blit buffer
	return;
    }
    
    // wipe update
    wipe_EndScreen(0, 0, SCREENWIDTH, SCREENHEIGHT);

    wipestart = I_GetTime () - 1;

    do
    {
	do
	{
	    nowtime = I_GetTime ();
	    tics = nowtime - wipestart;
	} while (!tics);
	wipestart = nowtime;
	done = wipe_ScreenWipe(wipe_Melt
			       , 0, 0, SCREENWIDTH, SCREENHEIGHT, tics);
	I_UpdateNoBlit ();
	M_Drawer ();                            // menu is drawn even on top of wipes
	I_FinishUpdate ();                      // page flip or blit buffer
    } while (!done);
}



//
//  D_DoomLoop
//
extern  boolean         demorecording;

extern void DebugPrint(char *str);

void D_DoomLoop (void)
{
    if (demorecording)
	G_BeginRecording ();

    I_InitGraphics ();

    while (1)
    {
      // frame syncronous IO operations
      I_StartFrame ();                

      // process one or more tics
      if (singletics)
	{
	  I_StartTic ();
	  D_ProcessEvents ();
	  G_BuildTiccmd (&netcmds[consoleplayer][maketic%BACKUPTICS]);
	  if (advancedemo)
	    D_DoAdvanceDemo ();
	  M_Ticker ();
	  G_Ticker ();
	  gametic++;
	  maketic++;
	}
      else
	{
	  TryRunTics (); // will run at least one tic
	}
		
      // Update display, next frame, with current state.
      D_Display ();
    }
}



//
//  DEMO LOOP
//
int             demosequence;
int             pagetic;
char                    *pagename;


//
// D_PageTicker
// Handles timing for warped projection
//
void D_PageTicker (void)
{
    if (--pagetic < 0)
	D_AdvanceDemo ();
}



//
// D_PageDrawer
//
void D_PageDrawer (void)
{
    V_DrawPatch (0,0, 0, W_CacheLumpName(pagename, PU_CACHE));
}


//
// D_AdvanceDemo
// Called after each demo or intro demosequence finishes
//
void D_AdvanceDemo (void)
{
    advancedemo = true;
}


//
// This cycles through the demo sequences.
// FIXME - version dependend demo numbers?
//
 void D_DoAdvanceDemo (void)
{
    players[consoleplayer].playerstate = PST_LIVE;  // not reborn
    advancedemo = false;
    usergame = false;               // no save / end game here
    paused = false;
    gameaction = ga_nothing;

    demosequence = (demosequence+1)%7;
    
    switch (demosequence)
    {
      case 0:
	pagetic = 170;
	gamestate = GS_DEMOSCREEN;
	pagename = "TITLEPIC";
	break;
      case 1:
	G_DeferedPlayDemo ("demo1");
	break;
      case 2:
	pagetic = 200;
	gamestate = GS_DEMOSCREEN;
	pagename = "CREDIT";
	break;
      case 3:
	G_DeferedPlayDemo ("demo2");
	break;
      case 4:
	gamestate = GS_DEMOSCREEN;
	pagetic = 200;
	pagename = "CREDIT";
	break;
      case 5:
	G_DeferedPlayDemo ("demo3");
	break;
        // THE DEFINITIVE DOOM Special Edition demo
      case 6:
	G_DeferedPlayDemo ("demo4");
	break;
    }
}



//
// D_StartTitle
//
void D_StartTitle (void)
{
    gameaction = ga_nothing;
    demosequence = -1;
    D_AdvanceDemo ();
}




//      print title for every printed line
char            title[128];



//
// D_AddFile
//
void D_AddFile (char *file)
{
    int     numwadfiles;
    char    *newfile;
	
    for (numwadfiles = 0 ; wadfiles[numwadfiles] ; numwadfiles++)
	;

    newfile = malloc (strlen(file)+1);
    strcpy (newfile, file);
	
    wadfiles[numwadfiles] = newfile;
}

//
// IdentifyVersion
// Checks availability of IWAD files by name,
// to determine whether registered/commercial features
// should be executed (notably loading PWAD's).
//
void IdentifyVersion (void)
{
  static char	doomwad[] = "/wad/doomu.wad";
  // Registered.
  D_AddFile (doomwad);
}

//
// D_DoomMain
//
void D_DoomMain (void)
{
    IdentifyVersion ();
	
    setbuf (stdout, NULL);
    modifiedgame = false;

    nomonsters = 0;
    respawnparm = 0;
    fastparm = 0;
    devparm = 0;
    
    sprintf (title,
	     "                         "
	     "The Ultimate DOOM Startup v%i.%i"
	     "                           ",
	     VERSION/100,VERSION%100);
    
    printf ("%s\n",title);

    // get skill / episode / map from parms
    startskill = sk_medium;
    startepisode = 1;
    startmap = 1;
    autostart = false;

    // init subsystems
    printf ("V_Init: allocate screens.\n");
    V_Init ();

    printf ("M_LoadDefaults: Load system defaults.\n");
    M_LoadDefaults ();              // load before initing other systems

    printf ("Z_Init: Init zone memory allocation daemon. \n");
    Z_Init ();

    printf ("W_Init: Init WADfiles.\n");
    W_InitMultipleFiles (wadfiles);
    
    printf ("M_Init: Init miscellaneous info.\n");
    M_Init ();

    printf ("R_Init: Init DOOM refresh daemon - ");
    R_Init ();

    printf ("\nP_Init: Init Playloop state.\n");
    P_Init ();

    printf ("I_Init: Setting up machine state.\n");
    I_Init ();

    printf ("D_CheckNetGame: Checking network game status.\n");
    D_CheckNetGame ();

    printf ("HU_Init: Setting up heads up display.\n");
    HU_Init ();

    printf ("ST_Init: Init status bar.\n");
    ST_Init ();

    if (gameaction != ga_loadgame) {
      if (autostart || netgame)
	G_InitNew(startskill, startepisode, startmap);
      else
	D_StartTitle();
    }
    
    D_DoomLoop ();  // never returns
}
